Transcript Typhoon Vamei talk - Naval Postgraduate School

Thesis Topics
Prof. C.-P. Chang
Tropical and Monsoon Meteorology
 Focus on the area of Indian Ocean-AsiaAustralia-Pacific
 All topics on Weather and Climate in this area
(all spatial and time scales)
 Data Analysis (NWP analysis, satellite data)
 General Circulation Model Simulation
Current Focuses
 East Asian Summer Monsoon (Meiyu weather
system in China/Japan/Korea and vicinity
 East Asian Winter Monsoon, particularly on
Maritime Continent Rainfall (Local, seasonal
and climate variations of rainfall over
Malaysia/Indonesia and vicinity)
 Equatorial Tropical Cyclones
East Asian Summer Monsoon
Onset of phased
Monsoon rainbelt
Subtropical
High
SCS
MJO
Monsoon
Onset
Convective
systems
East Asian Winter Monsoon
Cold
Surges
MJO
Subtropical High
Convective
systems
Equatorial TC: Typhoon Vamei 2001
center at 1.5N, lowest latitude record
GMS V 12/27/2001 0232 UTC
5N
5N
KUALA LUMPUR


BORNEO
ISLAND
Chang et al
2003, See
Poster
outside R251
SINGAPORE
EQ
EQ
SUMATRA
ISLAND
105E
110E
No TC Formation at the Equator?
 A classic formation criterion: 5 degrees away
from equator (e.g., Gray, 1968, Anthes, 1982)
 The lowest latitude of previously recorded
development: Typhoon Sarah in 1956 (3.3°N)
 Reason: Coriolis effect needed for initial spinup
d
( f   )  ( f   )  V
dt
NOGAPS 850hPa Wind and Vorticity
(red
+, green -)
QuikSCAT Winds
12N
12/26/2001 22:32 UTC
10N
8N
6N
4N
2N
+
BORNEO
ISLAND
EQ
SUMATRA
ISLAND
2S 102E
104E
106E
108E
110E
112E
Topic on Equatorial Tropical Cyclone
 Will more frequent development be
observed with increased remote sensing?
 Can equatorial formation occur
elsewhere? (Surges are strongest in the
South China Sea).
 Mechanism of development.
Approach
– Analyze recently observed equatorial
vortices:
 NWP gridded data: NOGAPS, NCEP,
ECMWF
 Scatterometer Ocean surface winds:
QuikSTAT
 Satellite Data: Hourly IR, MODIS images,
TRMM PR
Typhoon Agni 2004
Typhoon Agni 2004
EQ
EQ
60E
NOGAP 1000 hPa Wind
EQ
EQ
70E